Blast-feed stoker.



W. T. HANNA. BLAST FEED STOKER. APPLIOATION FILED APR. 28, 1910. RENEWED JAN. 26, 1911 'Patenfied Sept. 5, 1911'.

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WILLIAM '1. HANEA, OF CINCINNATI, OHIO.

BLAST-FEED STOKER.

Application filed April 28, 1910, Serial No.' 558,209.

T 0 all whom it may concern:

lie it known that l, WVILLIAM'T. I"IANNA,\& citizen of the United States, residing at Cincinnati, in the county of Hamilton and State of @hio, have invented a new and useful Improvement in Blast-Feed Stokers, of which the following is a specification;

In blast feed stokers the coal, usually varying in size from the smallest particle up to lumps three inches or more in diameter, is brought within range of the blast either in a stream or in charges, and the blast engages the fine particles and the coarse lumps with like pressure. The result is that the fine particles are driven farther into the fire box than the coarser lumps, and that the fuel bed is largely composed of coarse coal at the back and fine coal at the front or flue end, the intervening part being graduated from coarse to fine. If the blast is powerful some/of the finer particles pass into the fines without being consumed; if the blast is Weak the front of the fire box is lHSUlllciently fed. It is desirable to have the fine and the coarse coal distributed with ractical uniformity, and it is especially desir able to avoid delivering an undue proportion of the fine coal at the flue end of the fire box.

The object of my invention is to provide mechanism whereby the delivery of the fine, and the coarse coal may be separately controlled, and-whereby they may be mingled in the fire box with practical uniformity, and my invention consists in the parts and combination and arrangement of parts hereinafter described and claimed.

In the drawings, Figure 1 is a top plan view of a blast casing embodying my invention; Fig. 2 a front elevation of the same; Fig. 3 a horizontal section on the line 33 of Fig. 2; Fig. 4 a side elevation; Fig. 5 a vertical section on the line 55 of Fig. l; and Fig. (i a horizontal section showing a modified form' of the casing.

The reference numeral 1 denotes a blast casing, the upper face of which forms the spreading and delivery plate; 2 a series of sloping and diverging ridges, on the upper front face of the blast casing forming sloping and deepening channels 3; 4 and 5 steam chambers in the blast casing constituting respectively high and low pressure chambers; 6 and 7 steam inlet pipes leading respectively to the high and low pressure chambers; 8 "team exits in the apices of the Specification of Letters Patent.

Patented Sept. 5, 1911.

Renewed January 26, 1911. Serial No. 604,891.

In operation the coal is fed by any suit-' able mechanism to the front upper edge of the blast casing. The finer coal falls into the channels and, as it is discharged from the lower ends thereof, comes in range of blasts from steam exits 9; the larger lumps of coal ride down the ridges and, as they drop from the lower ends, come in range of the blasts from steamexits 8. The finer coal flows down the channels and, as it passes therefrom, comes in range of the blasts from. steam exits 9. By applying a comparatively powerful blast to the Coarse coal and a com paratively Weak blastto the finer coal, at proper mingling and distribution of the coal in the fire box may be obtained. Anv

desired means may be employed for regulating the intensity of the blasts. When a single blast, or line of blasts, is used a portion of the fine fuel is driven forwardly and upwardly and part ofit goes into the fines.

lVhen the fine fuel is separated from the coarse and two lines of blasts are used, an"

upper blast for the coarse fuel and a lower blast for the fine, the upper blast keeps the fine fuel down and prevents it from getting into the fines.

I claim as my invention:

1. In fuel feeding mechanism for stokcrs, the combination of means for separating the coarse from the fine fuel, and means for applying a comparatively powerful blast to the coarse fuel and a comparatively Weak blast to the fine fuel.

2. In fuel feeding mechanism for stokers, the combination of a spreading plate and channels for separating the coarse from the fine fuel, with one or moresteam chambers provided with steam exits adapted to deliver a comparatively powerful blast to the coarse fuel and a comparatively weak blast to the fine fuel.

, 3. In fuel feeding mechanism for stokers. the combination of a spreading plate having a series of ridges and channels for separating the coarse from the fine fuel; one or more steam chambers having separate exits adapted to deliver a blast of steam against the coarse fuel, and a blast of steam against I the combination of a spreading plate, having a series of sloping and diverging ridges and channels for separating the coarse from the fine fuel; a steam chamber having exits adapted to deliver a blast of steam against the coarse fuel, and a steam chamber having exits adaptedfto deliver a blast against the fine fuel.

WILLIAM T. HANNA.

i Witnesses:

W. W. SYMMES, HARRY Y, WALTON. 

